Merge tag 'ovl-update-5.6' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs

Pull overlayfs update from Miklos Szeredi:

 - Try to preserve holes in sparse files when copying up, thus saving
   disk space and improving performance.

 - Fix a performance regression introduced in v4.19 by preserving
   asynchronicity of IO when fowarding to underlying layers. Add VFS
   helpers to submit async iocbs.

 - Fix a regression in lseek(2) introduced in v4.19 that breaks >2G
   seeks on 32bit kernels.

 - Fix a corner case where st_ino/st_dev was not preserved across copy
   up.

 - Miscellaneous fixes and cleanups.

* tag 'ovl-update-5.6' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs:
  ovl: fix lseek overflow on 32bit
  ovl: add splice file read write helper
  ovl: implement async IO routines
  vfs: add vfs_iocb_iter_[read|write] helper functions
  ovl: layer is const
  ovl: fix corner case of non-constant st_dev;st_ino
  ovl: fix corner case of conflicting lower layer uuid
  ovl: generalize the lower_fs[] array
  ovl: simplify ovl_same_sb() helper
  ovl: generalize the lower_layers[] array
  ovl: improving copy-up efficiency for big sparse file
  ovl: use ovl_inode_lock in ovl_llseek()
  ovl: use pr_fmt auto generate prefix
  ovl: fix wrong WARN_ON() in ovl_cache_update_ino()

1 files changed, 14 insertions, 8 deletions

diff --git a/fs/overlayfs/readdir.c b/fs/overlayfs/readdir.c
index 47a91c9733a5..40ac9ce2465a 100644
--- a/fs/overlayfs/readdir.c
+++ b/fs/overlayfs/readdir.c
@@ -441,7 +441,7 @@ static u64 ovl_remap_lower_ino(u64 ino, int xinobits, int fsid,
 			       const char *name, int namelen)
 {
 	if (ino >> (64 - xinobits)) {
-		pr_warn_ratelimited("overlayfs: d_ino too big (%.*s, ino=%llu, xinobits=%d)\n",
+		pr_warn_ratelimited("d_ino too big (%.*s, ino=%llu, xinobits=%d)\n",
 				    namelen, name, ino, xinobits);
 		return ino;
 	}
@@ -469,7 +469,7 @@ static int ovl_cache_update_ino(struct path *path, struct ovl_cache_entry *p)
 	int xinobits = ovl_xino_bits(dir->d_sb);
 	int err = 0;
 
-	if (!ovl_same_sb(dir->d_sb) && !xinobits)
+	if (!ovl_same_dev(dir->d_sb))
 		goto out;
 
 	if (p->name[0] == '.') {
@@ -504,7 +504,13 @@ get:
 		if (err)
 			goto fail;
 
-		WARN_ON_ONCE(dir->d_sb->s_dev != stat.dev);
+		/*
+		 * Directory inode is always on overlay st_dev.
+		 * Non-dir with ovl_same_dev() could be on pseudo st_dev in case
+		 * of xino bits overflow.
+		 */
+		WARN_ON_ONCE(S_ISDIR(stat.mode) &&
+			     dir->d_sb->s_dev != stat.dev);
 		ino = stat.ino;
 	} else if (xinobits && !OVL_TYPE_UPPER(type)) {
 		ino = ovl_remap_lower_ino(ino, xinobits,
@@ -518,7 +524,7 @@ out:
 	return err;
 
 fail:
-	pr_warn_ratelimited("overlayfs: failed to look up (%s) for ino (%i)\n",
+	pr_warn_ratelimited("failed to look up (%s) for ino (%i)\n",
 			    p->name, err);
 	goto out;
 }
@@ -685,7 +691,7 @@ static int ovl_iterate_real(struct file *file, struct dir_context *ctx)
 	int err;
 	struct ovl_dir_file *od = file->private_data;
 	struct dentry *dir = file->f_path.dentry;
-	struct ovl_layer *lower_layer = ovl_layer_lower(dir);
+	const struct ovl_layer *lower_layer = ovl_layer_lower(dir);
 	struct ovl_readdir_translate rdt = {
 		.ctx.actor = ovl_fill_real,
 		.orig_ctx = ctx,
@@ -738,7 +744,7 @@ static int ovl_iterate(struct file *file, struct dir_context *ctx)
 		 * entries.
 		 */
 		if (ovl_xino_bits(dentry->d_sb) ||
-		    (ovl_same_sb(dentry->d_sb) &&
+		    (ovl_same_fs(dentry->d_sb) &&
 		     (ovl_is_impure_dir(file) ||
 		      OVL_TYPE_MERGE(ovl_path_type(dentry->d_parent))))) {
 			return ovl_iterate_real(file, ctx);
@@ -965,7 +971,7 @@ void ovl_cleanup_whiteouts(struct dentry *upper, struct list_head *list)
 
 		dentry = lookup_one_len(p->name, upper, p->len);
 		if (IS_ERR(dentry)) {
-			pr_err("overlayfs: lookup '%s/%.*s' failed (%i)\n",
+			pr_err("lookup '%s/%.*s' failed (%i)\n",
 			       upper->d_name.name, p->len, p->name,
 			       (int) PTR_ERR(dentry));
 			continue;
@@ -1147,6 +1153,6 @@ next:
 out:
 	ovl_cache_free(&list);
 	if (err)
-		pr_err("overlayfs: failed index dir cleanup (%i)\n", err);
+		pr_err("failed index dir cleanup (%i)\n", err);
 	return err;
 }